JPS60249004A - Weld zone detector - Google Patents

Abstract

PURPOSE:To deteact the weld zone of a shet material without providing a hole thereto by providing an arithmetic unit which calculates the change in the width of the sheet material from an image detector and travel detector as a function of the longitudinal position of the sheet material and a discriminating device which detects the weld zone from the detected change value thereof. CONSTITUTION:A weld zone detector is provided with the image detector 5 disposed in the position of the image of the sheet material formed by a lens system 4. The travel detector 6 which generates the signal corresponding to the extent of the movement of the sheet material according to the rotation of a roll is connected to the arithmetic unit 7. The signal information of the detector 6 is inputted to the unit 7. The unit 7 outputs the information on the sheet width as the longitudinal function of the sheet. The discriminating device 8 receives the output from the unit 7 as a change rate in the longitudinal direction, compares said output with a preset boundary value and generates a signal by discriminating that the weld zone is detected when the change rate exceeds said value. The weld zone is thus discriminated from the presence or absence of a notch without drilling a hole thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a weld detection device for detecting connections (welds) between metal plates processed in a continuous rolling mill.

[Technical background of the invention and its problems] In equipment for pickling, rolling, or annealing plate materials, especially metal plates, in order to achieve high productivity, it is necessary to continuously process the plates at the input side of the plate materials. There is a need to connect and operate the central processing equipment without stopping it.
There is a need to detect the connected parts because the connected plates have different processing specifications or there are strength problems at the joints that require special insulating operations. In particular, in equipment called a fully continuous rolling mill, which is equipped with a welding machine on the input side of the plate material and performs processing continuously without stopping or slowing down, various settings of the rolling mill are If changes are not made in accordance with passing, not only will the number of out-of-specification products, known as off-gauge products, increase, but it may also lead to serious problems such as board breakage. Therefore, it is important to accurately detect the weld. However, even at the welding points that S- knew were accurately welded by the welding machine, rolling continued while the plate was being transported to the rolling mill, even when the input side stopped for welding, etc. The material passes through an accumulation device such as a loop car, and its path length changes from time to time, or unexpected slippage occurs between the board and the transport roll.
Near the rolling mill, it is difficult to determine the location of the welding point based solely on the feed rate of the plate material.

Therefore, in order to detect the welding point, it has traditionally been done to drill a hole near the weld during welding and use an optical detector to detect this. There was a problem in that the risk of sheet breakage was increased, especially during rolling mill processing operations.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and its purpose is to provide a welded part detection device that can reliably detect a welded part without providing a hole in the vicinity of the welded part. It is in.

[Summary of the Invention] In order to achieve the above object, the present invention provides equipment for illuminating from one side of a traveling plate, a lens system placed on the other side of the plate, and an image placed in the image formed by this lens system. a detector;
a running detector for detecting the running of the board; an arithmetic device for calculating a change in the width of the board as a function of the longitudinal position of the board from the image detector and the running detector; A welding part detection device includes a determination device for detecting a welded part from a boundary value determined by the boundary value.

FIG. 1 shows an embodiment of the present invention.

1 is a roll that rotates in contact with a traveling plate material 2;

A light source 3 is arranged on the lower surface side of the plate material 2. Then, on the opposite side of the plate material 2 from the light source, there is a lens system 4, and an image detector 5 that detects an image placed at the position of the image of the plate material created by the lens system. A running detector 6 is connected to generate a signal corresponding to the amount of movement of the plate as the plate rotates. For example, a pulse generator,
Image information from the detector 5 and signal information from the travel detector 6 are input to an arithmetic unit 7. This arithmetic device 7 then outputs board width information as a function of the longitudinal direction of the board. This determination device takes the output of the calculation device 7 as the amount of change in the longitudinal direction, compares it with a preset boundary value, and when the value exceeds the value, determines that a welded portion has been detected and generates a signal.

The size and the position of the lens 4 are determined so that there is always a part that can be seen from the position of the lens, even if changes in the width of the light source 3tj plate material 1 and left and right deviations during traveling are taken into account. Then the gI of the board! is captured by the lens 4 as a shadow with bright areas of the light source on both sides, forming a real image.

The image detector 5 is placed at the real image position for detecting changes in plate width. As the image detector 5, a one-dimensional image sensor having a length that covers the range of the light source is suitable.

Since the image sensor configured with a COD or the like outputs a pulse train corresponding to bright and dark areas, the arithmetic unit 7 can easily determine the value of the plate width with appropriate accuracy. Traveling detector 6
When the signal from the image detector 5 is captured by the pulse signal output from the image detector 5 according to the amount of movement of the plate, it becomes the plate width as a function value depending on the position in the longitudinal direction of the plate. If you look at the shape of the notch on the board, it has a radius of 15 mm on each side, for example.
It is an arc with a depth of 5 cm in centimeters.

Factors that cause variations in the width of the board include fluctuations in the width itself and the edges of the board, but the former is within a few millimeters and the latter is within a range of several millimeters in the longitudinal direction, so for example, between 5 centimeters. If a criterion such as a change of 3 centimeters is given to the determination device 8, the determination device 8 can easily detect a notch, that is, a weld.0 Thus, by being able to determine a weld by the presence or absence of a notch, the strength of the material is reduced. There is no need to drill holes for
This is of great benefit to the operation of continuous processing equipment.

The above discussion has focused on welded parts of metal plates, but it can be applied to any material that blocks light, and the connection method is not limited to welding, but can also be applied to any connection method that applies a notch to shape the edge of the connection part. Applicable.

[Effects of the Invention] As explained above, according to the present invention, it is possible to provide a welding point detection device that can reliably detect a welded portion without providing a hole in the vicinity of the welded portion.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an embodiment of the present invention. 1... Plate material 2... Roll 3... Light source 4... Lens system 5... Image detector 6... Running detector 7... Arithmetic device 8... Judgment device agent Patent attorney Shi Nori Chika Kensuke (1 person) Figure 1

Claims (1)

[Claims] equipment that illuminates from one side of the traveling plate; a lens system disposed on the other side of the plate; an image detector placed on the image formed by the lens system; and a travel detector that detects the traveling of the plate;
an arithmetic device that calculates a change in the width of the plate material as a function of the longitudinal position of the plate material from the image detector and the travel detector; and a determination device that detects a welded part from the detected change value and a preset boundary value. A welding part detection device consisting of a device.